Cartridge-type lithium ion polymer battery pack

ABSTRACT

Disclosed is a cartridge-type lithium ion polymer battery pack including: at least two lithium ion polymer batteries in which adjacent electrode tabs are connected to each other so as to form a predetermined series circuit with a desired instrument; and an upper plate and a lower plate disposed at the top and the bottom of the whole lithium ion polymer batteries, respectively, and coupled to each other so that each lithium ion polymer battery is partially covered with them. Multiple layers of the battery packs are laminated and fixed with ease so as to conform to the electric power requirement for a desired instrument.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.10/965,334, filed on Oct. 14, 2004, which claims priority to KoreanPatent Application No. 10-2003-0071282, filed on Oct. 14, 2003, and allthe benefits accruing therefrom under 35 U.S.C. 119, the content ofwhich is herein incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a lithium ion polymer battery pack.More particularly, the present invention relates to a cartridge-typelithium ion polymer battery pack, wherein at least two pouch-shapedlithium ion polymer batteries are fixed with an upper plate and a lowerplate so as to be partially covered with the plates, thereby providing acartridge-type battery pack, and multiple layers of such cartridge-typebattery packs are laminated and connected to each other in series so asto conform to the electric power requirement for a desired instrumentand then are fixed detachably by means of bolts and nuts, or elasticfasteners.

BACKGROUND ART

In general, as shown in FIG. 1, a battery module 1 includes: a shell 2having a predetermined housing space that is open at the top and thebottom thereof; a battery assembly 6 having a plurality of cylindricalbatteries 3 disposed in such a manner that axis lines of the batteriesare parallel to each other, and battery retaining boards 5 disposed atthe top and the bottom of the whole batteries 3 so as to fix thebatteries 3 integrally by means of support bars 4; a lower cap 7 forfixing the lower battery retaining board 5 of the battery assembly 6 bymeans of the lower edge of the shell when the battery assembly 6 isinserted into the housing space of the shell 2; and an upper cap 8 forfixing the upper battery retaining board 5 of the battery assembly 6 bymeans of the upper edge of the shell 2.

Particularly, each of the lower cap 7 and the upper cap 8 is providedwith airflow ports 9 in order to discharge heat generated from eachbattery 3 in the battery assembly 6 to the exterior. Additionally, theupper cap 8 is provided with terminals 8 a at one side thereof so as tosupply electric current to an external instrument.

However, such a conventional battery module has a problem in thatbatteries forming a battery assembly have a cylindrical shape andrelatively large length and thus the whole volume of the battery moduleundesirably becomes large.

Further, because the battery assembly is large, it is not handy tolaminate and integrally fix a plurality of battery assemblies in orderto manufacture a battery module conformed to the electric powerrequirement for a desired instrument.

In another aspect, such a conventional battery module has a complicatedstructure because electrodes of each battery in a battery assembly areconnected via connectors on the battery retaining boards. Moreover,connecting electrodes of each battery via connectors on the batteryretaining boards is very cumbersome work.

Additionally, when multiple battery modules are laminated so as to beapplied as a power source for an instrument requiring high output (forexample a motor-drivable car), there is a great possibility of batteriesbeing overheated while the battery modules are operated for a long time,because batteries in a battery assembly forming a battery module are inclose contact with each other and surrounded with a shell.

DISCLOSURE OF THE INVENTION

Therefore, the present invention has been made in view of theabove-mentioned problems. It is an object of the present invention toprovide a cartridge-type lithium ion polymer battery pack, wherein aplurality of batteries are disposed in a predetermined unit to provide acartridge-type lithium ion polymer battery pack and multiple layers ofsuch cartridge-type lithium ion polymer battery packs are laminated soas to conform to the electric power requirement for a desired instrumentand then fixed with ease.

It is another object of the present invention to provide acartridge-type lithium ion polymer battery pack whose voltage andtemperature can be measured simply by connecting a desired PCB (printedcircuit board) to electrode tabs of lithium ion polymer batteries in thebattery pack.

It is still another object of the present invention to provide acartridge-type lithium ion polymer battery pack which can be used as apower source for an instrument requiring high output such as amotor-drivable car, in the form of multiple layers of battery packs thatcause heat generated from the battery packs to be discharged to theexterior efficiently.

According to an aspect of the present invention, there is provided acartridge-type battery pack including: at least two batteries in whichcorresponding electrode tabs are connected to each other connect with adesired instrument; and an upper plate and a lower plate disposed at thetop and the bottom of the whole lithium ion polymer batteries,respectively, and coupled to each other so that each lithium ion polymerbattery is partially covered with them.

According to another aspect of the present invention, there is provideda cartridge-type battery pack includes a battery; and an upper plate anda lower plate disposed at top and bottom of the battery, respectively,and coupled to each other so that the battery is partially covered withthem.

Herein, the term “instrument” is to be understood that it includes allof hybrid electric vehicles (HEV), electric vehicles (EV) and variousprime movers.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a schematic exploded perspective view showing a conventionalbattery module;

FIG. 2 is a schematic exploded perspective view showing a cartridge-typelithium ion polymer battery pack according to a preferred embodiment ofthe present invention;

FIG. 3 is a schematic perspective view showing a cartridge-type lithiumion polymer battery pack according to a preferred embodiment of thepresent invention;

FIG. 4 is a schematic perspective view showing the airflow path forcooling lithium ion polymer batteries in a cartridge-type lithium ionpolymer battery pack according to a preferred embodiment of the presentinvention;

FIG. 5 is a schematic perspective view showing how to laminate multiplelayers of cartridge-type lithium ion polymer battery packs according toa preferred embodiment of the present invention;

FIG. 6 is a partially enlarged schematic exploded perspective viewshowing the laminated structure of multiple layers of cartridge-typelithium ion polymer battery packs according to another preferredembodiment of the present invention, wherein two outer terminals betweenthe outermost battery of a first layer of battery pack and that of asecond layer of battery pack adjacent to the first layer are connectedin series; and

FIG. 7 is a schematic perspective view showing a cartridge-type lithiumion polymer battery pack as shown in FIG. 6.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention as shown in FIGS. 2 to 7.

FIG. 2 is a schematic exploded perspective view showing a cartridge-typelithium ion polymer battery pack according to a preferred embodiment ofthe present invention. FIG. 3 is a schematic perspective view showing acartridge-type lithium ion polymer battery pack according to a preferredembodiment of the present invention.

As shown in FIGS. 2 to 7, the battery pack according to the presentinvention includes: at least two lithium ion polymer batteries 11 inwhich adjacent electrode tabs 10 (or electrode terminals) are connectedto each other so as to form a predetermined series circuit with adesired instrument (not shown); and an upper plate 12 and a lower plate13 disposed at the top and the bottom of the whole lithium ion polymerbatteries, respectively, and coupled to each other so that each lithiumion polymer battery 11 is partially covered with them (See FIGS. 2 and3).

Particularly, each lithium ion polymer battery 11 may be fixed by meansof an adhesive coated on the surface facing to each of the upper plate12 and the lower plate 13. Otherwise, each lithium ion polymer battery11 may be fixed by a unique shape of each of the upper plate 12 and thelower plate 13.

When the lithium ion polymer battery 11 is fixed by a unique shape ofeach of the upper plate 12 and lower plate 13, it is preferable that oneof the upper plate 12 and the lower plate 13 has a plurality ofprotrusions 14 for engagement at predetermined intervals and the otherhas a plurality of holes 14 a for engagement corresponding to theprotrusions 14.

Preferably, a PCB 15 is disposed between the upper plate 12 and thelower plate 13, wherein the PCB 15 has a predetermined length and isprovided with wires each corresponding to a positive (+) pole and anegative (−) pole, each wire being connected to the correspondingelectrode tabs 10 of each lithium ion polymer battery 11 so that thevoltage and temperature of the battery can be measured.

Two outer electrode tabs 10 of two outermost batteries in the lithiumion polymer batteries 11 may be connected to outer electrode tabs 10 ofthe outermost batteries disposed at both sides of another adjacentbattery pack so as to form a series circuit with the lithium ion polymerbatteries in the adjacent battery pack. Such connection can be made bytwo corresponding conductive pieces 10 a, one having an upwardly bentouter end portion and the other having a downwardly bent outer endportion. In this case, remaining electrode tabs adjacent to each otherinside of the lithium ion polymer batteries 11 may be connected by meansof another plate-like conductive pieces 10 b.

Additionally, each of the upper plate 12 and the lower plate 13 may beprovided with cross members 17 disposed along the length of each plate12, 13, the cross members 17 being spaced apart from each other by apredetermined distance in the direction of width, so that lithium ionpolymer batteries 11 in each battery pack 16 can be partially exposed tothe exterior and cooled smoothly by the air when multiple layers ofbattery packs are laminated (See FIGS. 4 and 5).

In this case, each cross member 17 may be at least partially protrudedout from the surface of the lithium ion polymer battery 11 to which itis faced. Additionally, each cross member 17 may be provided with a slithole or a concave portion 17 a having a desired pattern for the purposeof reducing a weight increase resulting from lamination of multiplebattery packs 16 and preventing a so-called “sink” phenomenon, i.e., aphenomenon wherein the surface of an injection molded product looks tobe dented.

Further, it is preferable that at least a part of the cross members 17have through-holes 17 b at end edges thereof so that the battery pack 16or at least two battery packs 16 can be integrally fixed by means ofbolts and nuts.

In another embodiment, each of the upper plate 12 and the lower plate 13covering each lithium ion polymer battery 11 may be fixed with afastener (not shown) such as a clip having a predetermined elasticforce.

Meanwhile, in still another embodiment, two outer electrode tabs 10 oftwo outermost batteries in the lithium ion polymer batteries 11 may bepartially insert molded at both outermost ends in any one of the upperplate 12 and the lower plate 13 so as to form a series circuit withlithium ion polymer batteries of another adjacent battery pack.Particularly, two outer electrode tabs 10 of two outermost batteries inthe lithium ion polymer batteries 11 may be connected to outer electrodetabs 10 of the outermost batteries disposed at both sides of anotheradjacent battery pack by means of conductive insert members 18 partiallyexposed to the exterior and metal members (not shown) that aredetachable or fixed by welding in order to interconnect the outerexposed portions of the conductive insert members 18 (See, FIGS. 6 and7).

In this case, each conductive insert member 18 may include an innerportion 18 a to be connected to the outer electrode tab 10 of thecorresponding battery when they are assembled, a fixing portion 18 bhaving at least one fill-in hole 18 bb in which molten resin is filledduring insert molding, the fixing portion 18 b being formed integrallywith the inner portion 18 a, and a protrusion 18 c extending out fromthe fixing portion 18 b and connected to the metal member.

Hereinafter, the assembling process and operation of the above-describedcartridge-type lithium ion polymer battery pack according to presentinvention will be explained (See FIGS. 2 to 5).

First, a predetermined number of lithium ion polymer batteries aredisposed on a worktable (not shown). Then, electrode tabs 10 adjacent toeach other in each lithium ion polymer battery 11 are connected by meansof conductive pieces 10 a, 10 b sequentially.

Particularly, two outer electrode tabs 10 of the outermost batteriesdisposed at both sides of the lithium ion polymer batteries 11 areconnected to outer electrode tabs 10 of the outermost batteries disposedat both sides of another adjacent battery pack by means of twocorresponding conductive pieces 10 a, respectively.

Next, the upper plate 12 is disposed at one side of the whole lithiumion polymer batteries 11, the lower plate 13 being disposed at the otherside thereof. The upper and lower plates 12, 13 are fixed with anadhesive applied along the surface facing to them. Otherwise, the upperand lower plates 12, 13 are fixed by means of protrusions 14 and holes14 a for engagement (See FIGS. 2 and 3).

Meanwhile, for the purpose of measuring the voltage and temperature ofthe lithium ion polymer batteries 11 with ease, a PCB 15 is disposed onthe top of the whole lithium ion polymer batteries 11 so that it may bein contact with the electrode tabs 10 of each lithium ion polymerbattery or with the corresponding conductive piece 10 a, 10 b. Then, thelithium ion polymer batteries 11 may be fixed with the upper and lowerplates 12, 13.

Next, once a battery pack 16 including a unit having a plurality oflithium ion polymer batteries 11 is completely assembled, multiplelayers of battery packs 16 may be laminated to the number conformed tothe electric power requirement of a desired instrument (not shown).Next, such laminated battery packs may be fixed by inserting boltsthrough the through holes 17 b formed at the end edge of the crossmembers 17 in the upper and lower plates 12, 13 and securing the boltswith nuts. Otherwise, such laminated battery packs 16 may be fixed byusing elastic fasteners.

Particularly, both conductive pieces 10 a disposed at the outermostelectrode tabs 10 of the lithium ion polymer batteries 11 disposed atthe outermost sides of the battery pack 16 are fitted to wrap the edgeof the corresponding plate 12 or 13, one conductive piece being bentupwardly and the other being bent downwardly. Therefore, the upwardlybent conductive piece 10 a is connected to the electrode tab (orelectrode terminal) of the outermost lithium ion polymer battery 11 ofthe counterpart battery pack disposed on the top of the upwardly bentconductive piece 10 a. Similarly, the downwardly bent conductive piece10 a is connected to the electrode tab of the outermost lithium ionpolymer battery 11 of the counterpart battery pack disposed on thebottom of the downwardly bent conductive piece 10 a (See FIG. 5).

Meanwhile, when multiple battery packs are laminated for use as a powersource for instruments such as motor-drivable cars, a physical space isformed between one battery pack and another battery pack adjacentthereto by the cross members 17 formed at the outer sides of the upperand lower plates 12, 13 of each battery pack 16. Accordingly, lithiumion polymer batteries 11 surrounded by adjacent battery packs may becooled smoothly by the air circulated through the space formed betweenthe corresponding battery pack and another battery pack adjacent thereto(See FIGS. 4 and 5).

INDUSTRIAL APPLICABILITY

As can be seen from the foregoing, according to the present invention,multiple layers of the battery packs are laminated and fixed with easeso as to conform to the electric power requirement for a desiredinstrument.

Additionally, according to the present invention, it is possible tomeasure the voltage and temperature of a battery pack simply by means ofa PCB connected to the electrode tabs of each lithium ion polymerbattery in the battery pack.

Further, when multiple layers of battery packs are used as a powersource for an instrument requiring high output such as a motor-drivablecar, it is possible to discharge heat generated from the battery packsto the exterior efficiently.

While this invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not limited to thedisclosed embodiment and the drawings. On the contrary, it is intendedto cover various modifications and variations within the spirit andscope of the appended claims.

1. A cartridge-type battery pack comprising: a single battery; and anupper plate and a lower plate disposed at top and bottom of the battery,respectively, and coupled to each other so that the battery is partiallycovered with the upper plate and the lower plate, wherein each of theupper plate and the lower plate is provided with cross members disposedalong the length of each plate, the cross members being spaced apartfrom each other by a predetermined distance in the direction of width,so that the battery in the battery pack is partially exposed to theexterior for cooling, and at least a part of the cross members havethrough-holes at end edges thereof and the battery pack can beintegrally fixed by bolts and nuts via the through-holes.
 2. Thecartridge-type battery pack according to claim 1, wherein one of theupper plate and the lower plate has a plurality of protrusions forengagement at predetermined intervals and the other has a plurality ofholes for engagement corresponding to the protrusions.
 3. Thecartridge-type battery pack according to claim 1, wherein each crossmember is at least partially protruded out from the surface of thebattery to which it is faced, so that the batteries in each battery packcan be cooled smoothly by the air.
 4. The cartridge-type battery packaccording to claim 1, wherein the upper plate and the lower plate of thebattery pack are fixed with a fastener formed of an elastic material forfixing multiple battery packs integrally.
 5. The cartridge-type batterypack according to claim 1, wherein the battery is a lithium ion polymerbattery.